Global Astronomy Month:

One People, One Sky

an Exhibition

April 1, 2011 - April 30, 2011

The United Nations established the year 2009 as the International Year of Astronomy. The year marked the 400th anniversary of Galileo’s first use of the telescope to record his astronomical findings. In an effort to continue cultivating the spirit of collaboration across nations, the international astronomy organization Astronomers Without Borders has designated the month of April “Global Astronomy Month.” Its goal is to “bring new ideas, new opportunities and ... enthusiasts together worldwide, celebrating One People, One Sky.” The three books on display in this exhibition demonstrate how astronomers shared ideas, observations, findings and theories (even if not always correct) throughout the centuries, building upon each other’s work to make important contributions of their own. The two manuscripts on display are evidence of the enduring and pervasive fascination that studying the sky has had on amateur astronomers and enthusiasts.

Galileo Galilei (1564-1642) is considered the Father of modern mechanics. Galileo’s Dialogo (Dialogue Concerning the two Chief World Systems) is written as a conversation occurring over a four-day period between three characters, Salviati (representing Galileo arguing the Copernican model), Sagredo (neutral), and Simplicio (Aristotelian and Ptolemaic model). Reducing the argument to the simplest form, the Ptolemaic model asserts a geocentric universe, as opposed to Copernican heliocentric model that Galileo supported. The three characters are depicted in the woodcut shown here in this rare first edition. This work was suppressed by the inquisition in 1633. Galileo was suppose to renounce his work or be burned at the stake, neither of which happened. He was tried, found guilty and sentenced to a life under house arrest. Galileo was pardoned by the Catholic Church in 1922.

Pierre Gassendi (1592-1655) was a French philosopher and scientist.
This second edition of Gassendi’s book included a comprehensive
biography of the great astronomer Tycho Brahe (1546-1601). Brahe was one of the greatest observational scientists; working prior to the invention of a telescope, he used a quadrant to observe the sky. He made several important discoveries including a supernova (the birth of a new star), measured the shift (parallax) between stars, and could show how some stars were more distant than others, and much further than planets. Brahe’s model of the solar system was a combination of the Copernican and Ptolamaic theories. Although the model was incorrect, his observations on planetary motions formed the basis for Johannes Kepler’s work formulating the still current model of the solar system.

Sir Isaac Newton (1642-1727) was a great theorist and the inventor of
calculus. Principia played an extremely important role in the develop-
ment of modern mechanics and astronomy. Building upon the great
works by philosophers, mathematicians and astronomers including; Nicholas Copernicus, Galileo Galili, Johannes Kepler, and Rene Descartes, Newton developed three laws to show the causes of planetary motion and proved how the gravity of the sun pulls the planets which results in an orbit. The copy on display here is a rare first edition.

James Riddle Maxwell (1836-1912) was a civil engineer for the Pennsylvania, Northern and Pacific Railroads and a resident of Newark, Delaware. Between 1860 and 1862 he studied at Delaware College and Polytechnic College. Displayed here is his notebook from an astronomy class. His interest in astronomy continued after college: behind his course notes are additional astronomical observations he made in 1867, 1875 and 1876.

Archibald Wilson, a sailor in the 1840s who served aboard merchant
ships that made domestic and international voyages, kept a journal while at sea between 1842 and 1843. After the main journal entries, Wilson included “A Journal of Remarkable Incidents at Sea” in which he documented events observed between 1840 and 1842. In the entry shown here, Wilson writes about his experience on deck one night where he witnessed an extremely large and bright meteor or shooting star, which he writes was so bright “that it made me start back a little more scared than hurt, it seemed that the heaven had taken on fire.”